Various devices have been developed to sense the occurrence of nocturnal enuresis and to awaken the user upon detection of urine. Most of these devices are designed to be worn in the undergarments of the user. For example, see U.S. Pat. Nos. 2,687,721, 2,874,695, 3,460,123, 4,271,406, 4,653,491, 4,754,264 and 4,760,383. These devices are essentially signalling devices having an electrical circuit which is completed by the presence of urine thereby triggering an alarm.
U.S. Pat. No. 4,205,671 illustrates an enuresis sensor and a means for controlling the outflow. In addition to a sensor, this device is provided with means for supplying an electric shock to the nervous pudendus of the user thereby causing a contraction of a closing muscle in an attempt to prevent the discharge of urine.
A slightly different approach was taken in U.S. Pat. No. 3,810,140. Instead of activation of the alarm each and every time the user suffers enuresis, this device will only trigger the alarm 70 percent of the time. The object of this device is to provide an intermittent schedule of reinforcement instead of the continued reinforcement based on a theory of a lower relapse rate for users treated in this manner.
Similarly, U.S. Pat. No. 4,163,449 intends to "reward" the user for exercising control over enuresis. Upon initial detection of moisture, a noxious alarm is triggered. The alarm is terminated after a short period of time if the total amount of urine discharged is less than a given quantity, thereby rewarding the user.
Most of the prior art devices are designed for the treatment of primary nocturnal enuresis and do not consider prophylactic or symptom treatment or other forms of incontinence, including diurnal enuresis or combinations of physical and psychological causes of incontinence at all ages.
None of these prior art enuresis devices, however, utilize means for recording the events of wetting, to thereby develop a biofeedback training for the patient which can be used in combination with a signaling device for effectively assisting a wide range of patients in learning how to overcome the problem.